In aerial reconnaissance, cameras used must have the added flexibility of providing for film analysis, i.e., correlation with some previously defined symbols. For correlating, there is a need for obtaining a film record containing symbols representative of the target of interest. Also, to avoid having only one perspective of the view, for example only overhead views, there is a need for obtaining a record of the target of interest at different angles. After the target has been recorded onto film, there is further a need to analyze this film, to ascertain what the target represents. Consequently, the of interest film is indexed by frame (or orientation) for the purpose of fabricating any target matched filter at any orientation. The indexed film can then be played back at any orientation for any target or scene. For example, the selected scene can be rotated, thereby enabling the target--if present in the film--to be detected without resorting to a plurality of scenes having the same perspective. This indirectly increases the capacity of a correlator memory by not requiring the same to store all views, thereby freeing the memory to store other targets instead.
But in order to fabricate such target matched filter, and the subsequent comparison of targets therewith, a film drive mechanism has to be able to both translate and rotate. No such device exists prior to the present invention.
Further, since most of the targets are moving at the time records thereof are made, it is imperative that some mechanism be used to compensate for the blurring caused by the movement. A standard practice in aerial reconnaissance involves the use of elaborate optical and mechanical means. The present invention film driving mechanism eliminates the need for such elaborate means.